[%c_effect g8;square;g8;type;Interesting;persistent;true] A fantastic idea, and not new to this game. Black loses the right to castle, but prepares Bg6 to take with the h-pawn.
8. d1e1 [%c_effect e1;square;e1;type;Interesting;persistent;true] A subtle move. In addition to taking the knight out of the pin, White has another idea that will soon be revealed. 8... g8f6  9. f2f3  9... g4h5  10. e1h4 This is one of the points of White's play, although it's less dangerous than it seems at first sight.